The large spheres you see being pushed out of a human body by a surgeon in this video are Echinococcus larvae. Cystic Echinococcosis aka Hydatid Cyst is a parasitic disease the larvae of which can grow up to 10 cm (3 inches) in diameter within a year. Wikipedia says Cystic Echinococcosis can live inside its host for decades and grow so large, they contain liters of fluid. Humans get infected by Echinococcus worm after accidental digestion of the eggs. That can happen if one eats food after handling infected soil or feces and failing to wash their hands. If you have kids and want to make them start washing their hands before handling food, show them this video.